Fundamentals of Force-Controlled Friction Riveting: Part I—Joint Formation and Heat Development
Gonçalo Pina Cipriano,
Lucian A. Blaga,
Jorge F. dos Santos,
Pedro Vilaça,
Sergio T. Amancio-Filho
Affiliations
Gonçalo Pina Cipriano
Graz University of Technology, Institute of Materials Science, Joining and Forming, BMVIT Endowed Professorship for Aviation, 8010 Graz, Austria
Lucian A. Blaga
Helmholtz-Zentrum Geesthacht, Center for Materials and Coastal Research, Institute of Materials Research, Materials Mechanics, Solid State Joining Processes, 21502 Geesthacht, Germany
Jorge F. dos Santos
Helmholtz-Zentrum Geesthacht, Center for Materials and Coastal Research, Institute of Materials Research, Materials Mechanics, Solid State Joining Processes, 21502 Geesthacht, Germany
Pedro Vilaça
Department of Mechanical Engineering, School of Engineering, Aalto University, FI-00076 Espoo, Finland
Sergio T. Amancio-Filho
Graz University of Technology, Institute of Materials Science, Joining and Forming, BMVIT Endowed Professorship for Aviation, 8010 Graz, Austria
This work presents a systematic study on the correlations between process parameters and rivet plastic deformation, produced by force-controlled friction riveting. The 5 mm diameter AA2024 rivets were joined to 13 mm, nominal thickness, polyetherimide plates. A wide range of joint formations was obtained, reflecting the variation in total energy input (24⁻208 J) and process temperature (319⁻501 °C). The influence of the process parameters on joint formation was determined, using a central composite design and response surface methodology. Friction time displayed the highest contribution on both rivet penetration (61.9%) and anchoring depth (34.7%), and friction force on the maximum width of the deformed rivet tip (46.5%). Quadratic effects and two-way interactions were significant on rivet anchoring depth (29.8 and 20.8%, respectively). Bell-shaped rivet plastic deformation—high mechanical interlocking—results from moderate energy inputs (~100 J). These geometries are characterized by: rivet penetration depth of 7 to 9 mm; maximum width of the deformed rivet tip of 9 to 12 mm; and anchoring depth higher than 6 mm. This knowledge allows the production of optimized friction-riveted connections and a deeper understanding of the joining mechanisms, further discussed in Part II of this work.
